Every time I put files into on my PSP using my Mac I get errors. I was putting music on my PSP from my Mac to download onto the PS3. After the PS3 copied the files to the HD I plugged it back into my Mac to erase those files and add more. However when I erased the files the space is still taken up. Even though all the files are gone it is still showing I have a low amout of memory when in fact the card is cleared. I've already restored my memory card. Do I have to reformat my memory card EVERY time I use it with my Mac?! Has anyone else been getting this error? Is there any way to fix it at all or anything?